1/*
2 * Copyright (C) 2011 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1.  Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright
11 *     notice, this list of conditions and the following disclaimer in the
12 *     documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
17 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
21 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "AccessibilityScrollView.h"
28
29#include "AXObjectCache.h"
30#include "AccessibilityScrollbar.h"
31#include "Frame.h"
32#include "FrameView.h"
33#include "HTMLFrameOwnerElement.h"
34#include "RenderPart.h"
35#include "ScrollView.h"
36#include "Widget.h"
37
38namespace WebCore {
39
40AccessibilityScrollView::AccessibilityScrollView(ScrollView* view)
41    : m_scrollView(view)
42    , m_childrenDirty(false)
43{
44}
45
46AccessibilityScrollView::~AccessibilityScrollView()
47{
48    ASSERT(isDetached());
49}
50
51void AccessibilityScrollView::detach()
52{
53    AccessibilityObject::detach();
54    m_scrollView = 0;
55}
56
57PassRefPtr<AccessibilityScrollView> AccessibilityScrollView::create(ScrollView* view)
58{
59    return adoptRef(new AccessibilityScrollView(view));
60}
61
62AccessibilityObject* AccessibilityScrollView::scrollBar(AccessibilityOrientation orientation)
63{
64    updateScrollbars();
65
66    switch (orientation) {
67    case AccessibilityOrientationVertical:
68        return m_verticalScrollbar ? m_verticalScrollbar.get() : 0;
69    case AccessibilityOrientationHorizontal:
70        return m_horizontalScrollbar ? m_horizontalScrollbar.get() : 0;
71    }
72
73    return 0;
74}
75
76// If this is WebKit1 then the native scroll view needs to return the
77// AX information (because there are no scroll bar children in the ScrollView object in WK1).
78// In WebKit2, the ScrollView object will return the AX information (because there are no platform widgets).
79bool AccessibilityScrollView::isAttachment() const
80{
81    return m_scrollView && m_scrollView->platformWidget();
82}
83
84Widget* AccessibilityScrollView::widgetForAttachmentView() const
85{
86    return m_scrollView;
87}
88
89bool AccessibilityScrollView::canSetFocusAttribute() const
90{
91    AccessibilityObject* webArea = webAreaObject();
92    return webArea && webArea->canSetFocusAttribute();
93}
94
95bool AccessibilityScrollView::isFocused() const
96{
97    AccessibilityObject* webArea = webAreaObject();
98    return webArea && webArea->isFocused();
99}
100
101void AccessibilityScrollView::setFocused(bool focused)
102{
103    if (AccessibilityObject* webArea = webAreaObject())
104        webArea->setFocused(focused);
105}
106
107void AccessibilityScrollView::updateChildrenIfNecessary()
108{
109    if (m_childrenDirty)
110        clearChildren();
111
112    if (!m_haveChildren)
113        addChildren();
114
115    updateScrollbars();
116}
117
118void AccessibilityScrollView::updateScrollbars()
119{
120    if (!m_scrollView)
121        return;
122
123    if (m_scrollView->horizontalScrollbar() && !m_horizontalScrollbar)
124        m_horizontalScrollbar = addChildScrollbar(m_scrollView->horizontalScrollbar());
125    else if (!m_scrollView->horizontalScrollbar() && m_horizontalScrollbar) {
126        removeChildScrollbar(m_horizontalScrollbar.get());
127        m_horizontalScrollbar = 0;
128    }
129
130    if (m_scrollView->verticalScrollbar() && !m_verticalScrollbar)
131        m_verticalScrollbar = addChildScrollbar(m_scrollView->verticalScrollbar());
132    else if (!m_scrollView->verticalScrollbar() && m_verticalScrollbar) {
133        removeChildScrollbar(m_verticalScrollbar.get());
134        m_verticalScrollbar = 0;
135    }
136}
137
138void AccessibilityScrollView::removeChildScrollbar(AccessibilityObject* scrollbar)
139{
140    size_t pos = m_children.find(scrollbar);
141    if (pos != WTF::notFound) {
142        m_children[pos]->detachFromParent();
143        m_children.remove(pos);
144    }
145}
146
147AccessibilityScrollbar* AccessibilityScrollView::addChildScrollbar(Scrollbar* scrollbar)
148{
149    if (!scrollbar)
150        return 0;
151
152    AccessibilityScrollbar* scrollBarObject = static_cast<AccessibilityScrollbar*>(axObjectCache()->getOrCreate(scrollbar));
153    scrollBarObject->setParent(this);
154    m_children.append(scrollBarObject);
155    return scrollBarObject;
156}
157
158void AccessibilityScrollView::clearChildren()
159{
160    AccessibilityObject::clearChildren();
161    m_verticalScrollbar = 0;
162    m_horizontalScrollbar = 0;
163}
164
165bool AccessibilityScrollView::computeAccessibilityIsIgnored() const
166{
167    AccessibilityObject* webArea = webAreaObject();
168    if (!webArea)
169        return true;
170
171    return webArea->accessibilityIsIgnored();
172}
173
174void AccessibilityScrollView::addChildren()
175{
176    ASSERT(!m_haveChildren);
177    m_haveChildren = true;
178
179    AccessibilityObject* webArea = webAreaObject();
180    if (webArea && !webArea->accessibilityIsIgnored())
181        m_children.append(webArea);
182
183    updateScrollbars();
184}
185
186AccessibilityObject* AccessibilityScrollView::webAreaObject() const
187{
188    if (!m_scrollView || !m_scrollView->isFrameView())
189        return 0;
190
191    Document* doc = toFrameView(m_scrollView)->frame()->document();
192    if (!doc || !doc->renderer())
193        return 0;
194
195    return axObjectCache()->getOrCreate(doc);
196}
197
198AccessibilityObject* AccessibilityScrollView::accessibilityHitTest(const IntPoint& point) const
199{
200    AccessibilityObject* webArea = webAreaObject();
201    if (!webArea)
202        return 0;
203
204    if (m_horizontalScrollbar && m_horizontalScrollbar->elementRect().contains(point))
205        return m_horizontalScrollbar.get();
206    if (m_verticalScrollbar && m_verticalScrollbar->elementRect().contains(point))
207        return m_verticalScrollbar.get();
208
209    return webArea->accessibilityHitTest(point);
210}
211
212LayoutRect AccessibilityScrollView::elementRect() const
213{
214    if (!m_scrollView)
215        return LayoutRect();
216
217    return m_scrollView->frameRect();
218}
219
220FrameView* AccessibilityScrollView::documentFrameView() const
221{
222    if (!m_scrollView || !m_scrollView->isFrameView())
223        return 0;
224
225    return toFrameView(m_scrollView);
226}
227
228AccessibilityObject* AccessibilityScrollView::parentObject() const
229{
230    if (!m_scrollView || !m_scrollView->isFrameView())
231        return 0;
232
233    HTMLFrameOwnerElement* owner = toFrameView(m_scrollView)->frame()->ownerElement();
234    if (owner && owner->renderer())
235        return axObjectCache()->getOrCreate(owner);
236
237    return 0;
238}
239
240AccessibilityObject* AccessibilityScrollView::parentObjectIfExists() const
241{
242    if (!m_scrollView || !m_scrollView->isFrameView())
243        return 0;
244
245    HTMLFrameOwnerElement* owner = toFrameView(m_scrollView)->frame()->ownerElement();
246    if (owner && owner->renderer())
247        return axObjectCache()->get(owner);
248
249    return 0;
250}
251
252ScrollableArea* AccessibilityScrollView::getScrollableAreaIfScrollable() const
253{
254    return m_scrollView;
255}
256
257void AccessibilityScrollView::scrollTo(const IntPoint& point) const
258{
259    if (m_scrollView)
260        m_scrollView->setScrollPosition(point);
261}
262
263} // namespace WebCore
264